Luminaire



Nov. 16, 1965 D. E. HUSBY 3,218,450

LUMINAIRE Filed May 24, 1963 2 Sheets-Sheet 2 Fig.6. Fig.5.

Fig.7. Fig.8.

United States Patent 3,218,450 LUMINAERE Donald E. Hushy, Fairview Park, Ohio, assignor to Westinghonse Electric Corporation, East Pittsburgh, Pa, a corporation of Pennsylvania Filed May 24, 1963, Ser. No. 282,999 7 Claims. (Cl. 240-25) This invention relates, generally, to lighting fixtures and, more particularly, to a lamp socket and socket support for a luminaire which is utilized in streetlighting applications.

Streetlighting luminaires, particularly those utilizing a horizontal burning mercury vapor lamp, as manufactured heretofore have certain distribution characteristics, some of which are: (1) main beam elevation above nadir, (2) angular displacement of peak candlepower, (3) main beam width. The typing of distributions is further refined according to particular vertical zones, above nadir, to classify the distribution as (A) high angle, (E) medium angle, or (C) low angle, denoting long, medium or short-spaced units.

An object of this invention is to provide a luminaire having variable distribution characteristics.

Another object of the invention is to provide a means for controlling or altering points 1, 2 and 3 above, as well as provide adjustment from one vertical classifica tion to another of points A, B and C above.

A more general object of the invention is to provide a luminaire which shall be simple and eflicient in operation and which may be economically manufactured and installed.

Other objects of the invention will be explained fully hereinafter or will be apparent to those skilled in the art.

In accordance with one embodiment of the invention, a cylindrical socket for the lamp in a luminaire is rotatably clamped in a socket support. The center line of the socket opening or cavity for the lamp base and, there fore, the longitudinal axes of the lamp are angularly displaced a predetermined angle from the center line of the socket body. Also, a seat in a support for the lamp socket body is angularly displaced by the same angle as the socket opening with reference to its mounting surface. Thus, by rotating the socket in its support, the angular displacement of the lamp axis may be varied from zero degrees to twice the displacement angle. In this manner the distribution characteristics of the luminaire may be varied or adjusted by changing the location of the light center with reference to the reflector and the refractor of the luminaire.

For a better understanding of the nature and objects of the invention, reference may be had to the following detailed description, taken in conjunction with the accompanying drawings, in which:

FIGURE 1 is a view, partly in section and partly in side elevation, of a portion of a luminaire embodying the principal features of the invention;

FIG. 2 is a view, in end elevation, of a support for the lamp socket;

FIG. 3 is a view, in side elevation, of the socket support shown in FIG. 2;

FIG. 4 isa View, in side elevation, of a modified socket support;

FIG. 5 is a view, in longitudinal section, of the lamp socket utilized in the luminaire;

FIG. 6 is a view, in end elevation, of the lamp socket; and

FIGS. 7-10 are graphical views showing the manner in which the distribution characteristics of the luminaire may be varied by practicing the invention.

In P16. 1 of the drawings, there is shown a luminaire which may be generally of the type described in a coice pending application of W. M. Waldbauer, Serial No. 162,751, filed December 28, 1961, and assigned to the same assignee as the present application. Since the structure of the luminaire is completely illustrated and described in the aforesaid copending application, only a portion of the luminaire is shown and described in the present application. Briefly, the luminaire comprises a metal housing 21 a cover 21 which is removably attached to the housing 20, a ring 22 which is hinged on the housing 20 at 23 and supports a refractor 24, an inverted dished reflector 25, one end of which is supported by a bracket assembly 26 which is attached to the housing 20, and a lamp socket 27 which is also supported by the bracket assembly 26. A lamp 28, which may be of the mercury vapor type, is mounted in the lamp socket 27. The refractor ring 22, which carries the refractor 24 is retained in position by a latch assembly (not shown) located at the end of the refractor opposite the hinge support 23. The other end of the reflector 25 is also releasably retained in position by a spring member located opposite the end supported by the bracket assembly 26.

As explained hereinbefore, certain distribution characteristics of a luminaire have heretofore been determined by structural features of the luminaire and they could not be changed after the luminaire has been manufactured. In order to permit changing or varying certain of the distribution characteristics after manufacture and assembly of the luminaire, the lamp socket and support arrangement herein disclosed is provided. The lamp socket may be adjusted in its support to vary the distribution characteristics of the luminaire in the manner described hereinafter.

As shown most clearly in FIG. 5, the lamp socket comprises a generally cylindrical body 31 having a generally cylindrical opening or cavity 32 at one end for receiving the base of the lamp 28, an opening 33 at the other end for receiving electrical connecting members, and an integrally formed partition 34. The socket 31 is preferably composed of porcelain or other suitable insulating material. As shown, the longitudinal center line 35 of the opening 32 is displaced at an angle from the longitudinal center line 36 of the cylindrical socket body 31. By Way of example and not by limitation, the displacement angle is 3 as shown in the drawing. Since the opening 32 contains the lamp base, the longitudinal axis of the lamp is displaced by the angle of 3 As will be described hereinafter, the socket body 31 may be rotated in its support through 360 about the longitudinal center line 36 of the socket body. Therefore, if the socket body were rotated through 360 about its center line, the center line 35 of the opening 32 would describe a conical surface having a triangular cross section with an apex angle of twice the angular displacement or, in this case, 6.

Furthermore, by so constructing the support assembly 26 that it has a seat for the socket body 31 also angularly displaced by the same angle as the socket opening 32, in this case 3, the angular displacement of the lamp axis may be varied from zero degrees to twice the displacement angle, in this case from zero degrees to 6, by rotating the socket body through 360. As will be explained more fully hereinafter, this changes the position of the light center with reference to the reflector 25 and the refractor 24-, thereby varying the distribution characteristics of the luminaire.

If the seat for the socket body is not tilted or inclined, but is disposed at a right angle to the vertical leg of the bracket assembly 26, as shown in FIG. 4, the lamp axis may be tilted 3 above or below the reference line or the longitudinal center line of the socket body. The angular displacement of the lamp axis changes the position of the light center with reference to the reflector and the refractor, thereby varying the distribution characteristics of the luminaire as will be explained more fully hereinafter.

The structure of the bracket assembly 26 is shown most clearly in FIGS. 2 and 3. The assembly comprises an L-shaped plate or bracket having a vertical leg 41 and a horizontal leg 42, and a generally V-shaped seat or support 43 for receiving the lamp socket 31. The vertical leg has a round opening 44 therein through which the socket body 31 extends. The horizontal leg 42 may be attached to the housing by means of bolts 45 (FIG. 1). The seat 43 has downwardly extending angularly disposed legs 46, 47 and 48 which are attached to the vertical member 41 by welding or other suitable means. As shown in FIG. 3, the seat 43 is disposed at an angle of 87 from the vertical leg 41 or an angle of 3 with reference to the horizontal leg 42 of the bracket assembly. The socket body 31 is clamped in position on the seat 43 by means of an inverted generally U-shaped band 51 having outwardly extending ends 52 which may be attached to outwardly extending ends 53 on the seat 43 by means of screws or bolts 54 threaded into weld nuts 55 on the ends 53 of the seat 43. Thus, the socket body 31 may be rotated to any desired position by loosening the clamp 51 and then retained in that position by retightening the clamp by means of the bolts 54.

As explained hereinbefore, tilting or displacing the seat 43 at the 3 angle permits the lamp axis to be varied from zero degrees to 6 with reference to a line parallel to the horizontal leg 42 of the bracket assembly 26 which also functions to support and determine the position of the reflector 25. Thus, rotation of the lamp socket varies the position of the light center with reference to the reflector 25.

As shown in FIG. 1, the vertical leg 41 of the bracket assembly functions as a support for a gasket 56 which surrounds the lamp socket to support and determine the position of the reflector 25. I The gasket 56 is disposed in an opening 57 in the one end of the reflector and the socket body 31 projects through the opening 57 into the reflector 25. Thus, the position of the reflector is determined by the vertical leg 41 of the bracket assembly 26 and changing the position of the lamp axis with reference to the leg 41 changes the position of the lamp axis with reference to the reflector 25.

As explained hereinbefore, the seat 43 for the lamp socket may be disposed at an angle of 90 to the vertical leg 41. This arrangement is shown in FIG. 4. In this case, the lamp axis may be tilted 3 above or below the reference line by rotating the lamp socket 31 in its support.

The effect which the utilization of the present lamp socket and support has on the distribution characteristics of a particular luminaire may be understood by referring to FIGS. 7 and 8. The optical parameters of a typical luminaire are shown by the solid lines in these figures. The line LL represents the line of lamp axis in horizontal position which, in turn, causes a reflector beam of 69 above nadir and a refractor beam of 76. An angular change of 6 upward in the axial position of the lamp as shown by the line M-M in FIG. 7, that is raising the light center from 61 to 61' in the plane of the reflectorrefractor center line as shown in FIG. 8, produces a corresponding decrease in vertical beam direction with reference to the vertical. As shown, the angle of the beam is lowered from 76 to 70". Thus, various vertical distributions can be provided which are symmetrical on either side of the luminaire.

If desired, non-symmetrical beams may be provided side-to-side on one luminaire by utilizing the lamp socket and support herein described. As shown in FIGS. 9 and 10, if the socket is rotated to change the lamp axis and the light center from the position LL to the position N-N as shown in FIG. 9 or from 61 to 61" as shown in FIG. 10, the light beams are lowered On one side more than on the other side. As shown in FIG. 10, the beams are lowered from an angle of 76 to an angle of 72 on one side of the luminaire while on the opposite side they emerge at an angle of 74. Thus, in streetlighting, the beam can be lowered more on the drivers side to reduce the glare confronted by the motorist, whereas on the aWay-from-trafiic side, the beam elevation can be higher to achieve a somewhat greater spacing between luminaires.

The position of the lamp socket may also be adjusted longitudinally in its support. The adjustment of the socket and lamp longitudinally along its axis is widely practiced and well known. Therefore, this feature will not be explained in detail. Briefly, the movement of the lamp socket along its longitudinal axis increases or decreases the angular toe-in of the reflector-refractor main beams in an equal but opposite direction.

From the foregoing description, it is apparent that when the features of the present invention are utilized in conjunction with the ability to move the lamp socket longitudinally, the optical system of a luminaire has the flexibility to cover a relatively great range of street widths and contour as well as provide features of greater utility. By choosing the proper angular and dimensional parameters for a particular luminaire optical system, great flexibility can be achieved by utilizing the present socket and socket support construction.

Since numerous changes may be made in the above described construction, and different embodiments of the invention may be made without departing from the spirit and scope thereof, it is intended that all the subject matter contained in the foregoing description or shown in the accompanying drawing, shall be interpreted as illustrative and not in a limiting sense.

I claim as my invention:

1. In a luminaire, in combination, a housing, a reflector supported within the housing, and a refractor supported by the housing below the reflector,

a generally cylindrical socket for supporting a lamp between the reflector and the refractor,

said socket having a generally cylindrical cavity in the body portion thereof for receiving the lamp base,

a bracket attached to the housing for supporting the socket,

means for releasably retaining the socket in the bracket,

the center line of the socket cavity extending at a predetermined angle with reference to the longitudinal center line of the socket body, and

said socket being rotatable about its longitudinal center line to change the position of the lamp with reference to the reflector and the refractor and vary the distribution characteristics of the luminaire.

2. In a luminaire, in combination, a housing, a reflector supported Within the housing, and a refractor supported by the housing below the reflector,

a generally cylindrical socket for supporting a lamp between the reflector and the refractor,

said socket having a generally cylindrical cavity in the body portion thereof for receiving the lamp base,

a bracket attached to the housing for supporting the socket,

the center line of the socket cavity extending at a predetermined angle with reference to the longitudinal center line of the socket body,

said socket having a generally cylindrical cavity in the line to change the position of the lamp with reference to the reflector and the refractor and vary the distribution characteristics of the luminaire, and clamping means for retaining the socket in the bracket at any one of a plurality of predetermined positions.

3. In a luminaire, in combination, a housing, a reflector supported within the housing, and a refractor supported by the housing below the reflector,

a generally cylindrical socket for supporting a lamp between the reflector and the refractor,

said socket having a generally cylindrical cavity in the body portion thereof for receiving the lamp base,

the center line of the socket cavity extending at a predetermined angle of displacement with reference to the longitudinal center line of the socket body,

a bracket attached to the housing for supporting the socket body at an inclined angle with reference to the support for the reflector, and

said socket being rotatable about its longitudinal center line to change the position of the lamp with reference to the reflector and the refractor and vary the distribution characteristics of the luminaire.

4. In a luminaire, in combination, a housing, a reflector supported within the housing, and a refractor supported by the housing below the reflector,

a generally cylindrical socket for supporting a lamp between the reflector and the refractor,

said socket having a generally cylindrical cavity therein for receiving the lamp base,

the center line of the socket cavity extending at a predetermined angle of displacement with reference to the longitudinal center line of the socket body,

a bracket attached to the housing for supporting the socket body at an angle inclined to the support for the reflector substantially the same amount as the displacement angle between the center line of the socket cavity and the center line of the socket body, and

said socket body being rotatable to vary the angular displacement of the center line of the socket cavity from zero degrees to twice the displacement angle thereby varying the distribution characteristics of the luminaire.

5. In a luminaire, in combination, a housing, a reflector supported within the housing, and a refractor supported by the housing below the reflector,

a generally cylindrical socket for supporting a lamp between the reflector and the refractor,

said socket having a generally cylindrical cavity therein for receiving the lamp base,

the center line of the socket cavity extending at a predetermined angle of displacement with reference to the longitudinal center line of the socket body,

a bracket attached to the housing for supporting the socket body at an angle inclined to the support for the reflector substantially the same amount as the displacement angle between the center line of the socket cavity and the center line of the socket body, and

said socket body being rotatable about its longitudinal axis and movable along its longitudinal axis to change the position of the lamp with reference to the reflector and the refractor to vary the distribution characteristics of the luminaire.

6. In a luminaire the combination comprising:

a generally cylindrical lamp socket,

a support for said lamp socket,

an inverted dished reflector having an aperture at one end thereof through which said socket projects into said reflector,

a cavity in said lamp socket at the longitudinal end thereof which projects into said reflector, said cavity receiving and supporting the base of a lamp which is positioned with-in said reflector, the centerline of said cavity being slightly angularly displaced from the centerline of said lamp socket,

said lamp socket being rotatably mounted on said support about the longitudinal center axis of said lamp socket to vary the position of the centerline of said cavity and said lamp with respect to said reflector, which varies the light distribution characteristics of said luminaire.

7. The luminaire as specified in claim 6, wherein a releasable clamping means is provided for retaining the lamp socket in the support at any rotatable position.

References Cited by the Examiner UNITED STATES PATENTS 1,658,446 2/1928 Kuehner 240-442 1,756,530 4/1930 Aldeen 24044.2 X 3,065,338 11/1962 Husby et al 240-442 X NORTON ANSI-IER, Primary Examiner. 

6. IN A LUMINAIRE THE COMBINTION COMPRISING: A GENERALLY CYLINDRICAL LAMP SOCKET, A SUPPORT FOR SAID LAMP SOCKET, AN INVERTED DISHED REFLECTOR HAVING AN APERTURE AT ONE END THEREOF THROUGH WHICH SAID SOCKET PROJECTS INTO SAID REFLECTOR, A CAVITY IN SAID LAMP SOCKET AT THE LONGITUDINAL END THEREOF WHICH PROJECTS INTO SAID REFLECTOR, SAID CAVITY RECEIVING AND SUPPORTING THE BASE OF A LAMP WHICH IS POSITIONED WITHIN SAID REFLECTOR, THE CENTERLINE OF SAID CAVITY BEING SLIGHTLY ANGULARLY DISPLACED FROM THE CENTERLINE OF SAID LAMP SOCKET, SAID LAMP SOCKET BEING ROTATABLY MOUNTED ON SAID SUPPORT ABOUT THE LONGITUDINAL CENTER AXIS OF SAID LAMP SOCKET TO VARY THE POSITION OF THE CENTERLINE OF SAID CAVITY AND SAID LAMP WITH RESPECT TO SAID REFLECTOR, WHICH VARIES THE LIGHT DISTRIBUTION CHARACTERISTICS OF SAID LUMINAIRE. 